Therapeutic potential of larval excretory/secretory proteins of the pig whipworm Trichuris suis in allergic disease

BACKGROUND

Gastrointestinal nematodes are currently being evaluated as a novel therapeutic in the treatment of chronic human inflammatory disorders, due to their unique ability to induce immunoregulatory pathways in their hosts. In particular, administration of ova from the pig whipworm Trichuris suis (T. suis; TSO) has been proposed for the treatment of allergic, inflammatory and autoimmune disorders. Despite these advances, the biological pathways through which TSO therapy modulates the host immune system in the context of human disease remain undefined.

METHODS

We characterized the dominant proteins present in the excretory/secretory (E/S) products of first-stage (L1) T. suis larvae (Ts E/S) using LC-MS/MS analysis and examined the immunosuppressive properties of whole larval Ts E/S in vitro and in a murine model of allergic airway disease.

RESULTS

Administration of larval Ts E/S proteins in vivo during the allergen sensitization phase was sufficient to suppress airway hyperreactivity, bronchiolar inflammatory infiltrate and allergen-specific IgE production. Three proteins in larval Ts E/S were unambiguously identified. The immunomodulatory function of larval Ts E/S was found to be partially dependent on the immunoregulatory cytokine IL-10.

CONCLUSIONS

Taken together, these data demonstrate that the released proteins of larval T. suis have significant immunomodulatory capacities and efficiently dampen allergic airway hyperreactivity. Thus, the therapeutic potential of defined larval E/S proteins should be exploited for the treatment of human allergic disorders.

How Ebola virus counters the interferon system

Zoonotic transmission of Ebola virus (EBOV) to humans causes a severe haemorrhagic fever in afflicted individuals with high case-fatality rates. Neither vaccines nor therapeutics are at present available to combat EBOV infection, making the virus a potential threat to public health. To devise antiviral strategies, it is important to understand which components of the immune system could be effective against EBOV infection. The interferon (IFN) system constitutes a key innate defence against viral infections and prevents development of lethal disease in mice infected with EBOV strains not adapted to this host. Recent research revealed that expression of the host cell IFN-inducible transmembrane proteins 1-3 (IFITM1-3) and tetherin is induced by IFN and restricts EBOV infection, at least in cell culture model systems. IFITMs, tetherin and other effector molecules of the IFN system could thus pose a potent barrier against EBOV spread in humans. However, EBOV interferes with signalling events required for human cells to express these proteins. Here, we will review the strategies employed by EBOV to fight the IFN system, and we will discuss how IFITM proteins and tetherin inhibit EBOV infection.

Mechanisms and rescue strategies of calcineurin inhibitor mediated tolerance abrogation induced by anti-CD4 mAb treatment

To ensure safety tolerance induction protocols are accompanied by conventional immunosuppressive drugs (IS). But IS such as calcineurin inhibitors (CNI), for example, cyclosporin A (CsA), can interfere with tolerance induction. We investigated the effect of an additional transient CsA treatment on anti-CD4mAb-induced tolerance induction upon rat kidney transplantation. Additional CsA treatment induced deteriorated graft function, resulting in chronic rejection characterized by glomerulosclerosis, interstitial fibrosis, tubular atrophy and vascular changes. Microarray analysis revealed enhanced intragraft expression of the B cell attracting chemokine CXCL13 early during CsA treatment. Increase in CXCL13 expression is accompanied by enhanced B cell infiltration with local and systemic IgG production and C3d deposition as early as 5 days upon CsA withdrawal. Adding different CNIs to cultures of primary mesangial cells isolated from glomeruli resulted in a concentration-dependent increase in CXCL13 transcription. CsA in synergy with TNF-α can enhance the B cell attracting and activating potential of mesangial cells. Transient B cell depletion or transfer of splenocytes from tolerant recipients 3 weeks after transplantation could rescue tolerance induction and did inhibit intragraft B cell accumulation, alloantibody production and ameliorate chronic rejection.

Mesenteric fat - control site for bacterial translocation in colitis?

In Crohn's disease bacteria could be detected in the adjacent mesenteric fat characterized by hypertrophy of unknown function. This study aimed to define effector responses of this compartment induced by bacterial translocation during intestinal inflammation. Dextran sulfate sodium-induced colitis served as a model of intestinal inflammation. Translocation of peptides and bacteria into mesenteric fat was evaluated. Innate functions of mesenteric fat and epithelium were characterized at whole tissue, cellular, and effector molecule levels. Orally applied peptides translocated in healthy wild-type (WT) mice. Bacterial translocation was not detected in healthy and acute but increased in chronic colitis. Mesenteric fat from colitic mice released elevated levels of cytokines and was infiltrated by immune cells. In MyD88(-/-) mice bacterial translocation occurred in health and increased in colitis. The exaggerated cytokine production in mesenteric fat accompanying colonic inflammation in WT mice was less distinct in MyD88(-/-) mice. In vitro studies revealed that fat not only increases cytokine production following contact with bacterial products, but also that preadipocytes are potent phagocytes. Colonic inflammation is accompanied by massive cytokine production and immune cell infiltration in adjacent adipose tissue. These effects can be considered as protective mechanisms of the mesenteric fat in the defense of bacterial translocation.

Permanent CNI treatment for prevention of renal allograft rejection in sensitized hosts can be replaced by regulatory T cells

Recent data suggest that donor-specific memory T cells (T(mem)) are an independent risk factor for rejection and poor graft function in patients and a major challenge for immunosuppression minimizing strategies. Many tolerance induction protocols successfully proven in small animal models e.g. costimulatory blockade, T cell depletion failed in patients. Consequently, there is a need for more predictive transplant models to evaluate novel promising strategies, such as adoptive transfer of regulatory T cells (Treg). We established a clinically more relevant, life-supporting rat kidney transplant model using a high responder (DA to LEW) recipients that received donor-specific CD4(+)/ 8(+) GFP(+) T(mem) before transplantation to achieve similar pre-transplant frequencies of donor-specific T(mem) as seen in many patients. T cell depletion alone induced long-term graft survival in naïve recipients but could not prevent acute rejection in T(mem)(+) rats, like in patients. Only if T cell depletion was combined with permanent CNI-treatment, the intragraft inflammation, and acute/chronic allograft rejection could be controlled long-term. Remarkably, combining 10 days CNI treatment and adoptive transfer of Tregs (day 3) but not Treg alone also induced long-term graft survival and an intragraft tolerance profile (e.g. high TOAG-1) in T(mem)(+) rats. Our model allows evaluation of novel therapies under clinically relevant conditions.

Characterization of the recombinant Rieske [2Fe-2S] proteins HcaC and YeaW from E. coli

Three genes within the genome of E. coli K12 are predicted to encode proteins containing the typical Rieske iron-sulfur cluster-binding motifs. Two of these, hcaC and yeaW, were overexpressed in E. coli BL21 and Tuner (DE3) pLacI. The recombinant proteins were purified and analyzed by UV/Vis- and EPR-spectroscopy. HcaC and YeaW display the typical redox-dependent UV/Vis-spectra of iron-sulfur proteins. The EPR spectrum of reduced HcaC shows characteristic g-values of a Rieske cluster whereas the g-values for YeaW are close to the upper limit for this type of iron-sulfur cluster. Both iron-sulfur clusters could be reduced by dithionite, but not by ascorbate, confirming their classification as low-potential Rieske proteins as derived from the amino acid sequences. A phylogenetic analysis of the two proteins reveals that HcaC clearly segregates with the Rieske ferredoxins of class IIB oxygenases whereas the classification of YeaW remains doubtful.

Radial scar/complex sclerosing lesion of the breast--value of ultrasound

PURPOSE

Although benign, radial scar/complex sclerosing adenosis is a lesion which histopathologically resembles tubular carcinoma. On physical examination, it is difficult to distinguish radial scar from a malignant tumour. Mammography cannot differentiate radial scar from malignancy. This clinical study aims to delineate the role of preoperative ultrasonography with emphasis on the question whether ultrasonography could lower the number of false-positive readings and therefore the number of open biopsies required.

MATERIALS AND METHODS

In this examination, we present the clinical, mammographic, ultrasonographic, and histopathological features of 6 cases of radial scars.

RESULTS

Although most authors describe radial scars as non-palpable, 2 of 6 lesions were indeed palpable. On mammograms, radial scars have a spiculated appearance, a feature observed in all of our cases. Numerous ultrasonographic characteristics are listed in the literature, but ultrasonography is not reported to have clear-cut advantages.

CONCLUSION

Although this study did not elucidate any unique ultrasonographic features to characterise these lesions, the analysis of all ultrasonographic results made us recognise a set of "nearly specific ultrasonographic features" of radial scars. Current B-mode imaging does not appear to lead to the desirable reduction of the rate of unnecessary open biopsies.

Emergency medical service transport-induced stress? An experimental approach with healthy volunteers

This randomized controlled trial was designed to evaluate the effects of simulated emergency medical service (EMS) transport related stress on hemodynamic variables, and catecholamine plasma levels. A total of 32 healthy male volunteers were randomized to being carried by paramedics from a third-floor apartment through a staircase with subsequent high-speed EMS transport with lights and sirens (stress; n = 16); or sitting on a chair for 5 min, and lying on a stretcher for 15 min (control; n = 16). Blood samples and hemodynamic variables were taken in the apartment before transfer, at the ground floor, and at the end of EMS transport in the stress group, and at corresponding time points in the control group. The stress versus control group had both significantly (P < 0.05) higher mean +/- SEM epinephrine (71 +/- 7 versus 37 +/- 3 pg/ml), and norepinephrine (397 +/- 29 versus 299 +/- 28 pg/ml) plasma levels after transport through the staircase. After EMS transport, the stress versus control group had significantly higher epinephrine (48 +/-6 versus 32 +/- 2 pg/ml), but not norepinephrine (214 +/- 20 versus 264 +/- 31 pg/ml) plasma levels. Heart rate increased significantly from 72 +/- 2 to 84 +/- 3 bpm after staircase transport, but not during and after EMS transport. In conclusion, volunteers being carried by paramedics through a staircase had a significant discharge of both epinephrine and norepinephrine resulting in increased heart rate, but only elevated epinephrine plasma levels during EMS transport. Transport through a staircase may reflect more stress than emergency EMS transport.

Is there a beneficial effect of the calcium channel blocker diltiazem on cyclosporine A nephrotoxicity in rats?

To investigate whether or not there is a beneficial effect of diltiazem (D) on cyclosporine A (CsA) nephrotoxicity, renal function, CsA blood levels, and effects of CsA on biotransformation in the liver and on lipid peroxidation were characterized in rats. A single administration of D (60 mg/kg b.wt.) reduced urinary volume (UV), GFR and excretion of Na+ and K+, whereas a single dose of CsA (60 mg/kg b.wt.) alone had no respective effects. P-aminohippurate excretion was almost equal in all groups. Lower doses of D (and CsA) were without effects. After repeated CsA treatment a retardation in body weight gain was seen, with little effect of a co-administration with D hereon. In all tests, thymus mass was reduced by CsA, the weight of spleen, liver, adrenal glands, and kidney were not generally affected by any of the treatments. Furthermore, after repeated administration of CsA and/or D, urinary volume, GFR and Na+ excretion were reduced by CsA, too. Electrolyte concentrations in plasma showed no evident changes by any of the treatments for Na+ and Ca2+. After long time treatment, CsA and CsA + D quite similarly led to higher K+ but lower Mg2+ concentrations in plasma. Only with 7 days highest dosage treatment PAH excretion was reduced significantly by CsA and CsA + D treatment. Surprisingly, CsA levels measured in blood and in kidney tissue, showed lower values after co-administration with D compared to CsA treatment alone. This could be caused by higher activities of monooxygenase functions revealed after pretreatment with D alone. Reduced glutathione (GSH) contents in kidney were elevated in CsA and CsA + D treated groups. In general no significant differences were to be observed concerning lipid peroxidation and stimulated H2O2 formation. Altogether evident protective effects of diltiazem on CsA nephrotoxicity in rats could not be proven.